loop0: detected capacity change from 0 to 2048 ------------[ cut here ]------------ refcount_t: underflow; use-after-free. WARNING: CPU: 1 PID: 3038 at lib/refcount.c:87 refcount_dec_and_lock+0x180/0x1ec lib/refcount.c:146 Modules linked in: CPU: 1 PID: 3038 Comm: syz-executor274 Not tainted 6.0.0-rc7-syzkaller-18095-gbbed346d5a96 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022 pstate: 60400005 (nZCv daif +PAN -UAO -TCO -DIT -SSBS BTYPE=--) pc : refcount_dec_and_lock+0x180/0x1ec lib/refcount.c:146 lr : refcount_dec_not_one lib/refcount.c:87 [inline] lr : refcount_dec_and_lock+0x17c/0x1ec lib/refcount.c:146 sp : ffff800012893a30 x29: ffff800012893a30 x28: ffff80000cc15042 x27: ffff0000cc376640 x26: 0000000000000002 x25: 00000000ffffffff x24: 0000000000000000 x23: 00000000c0000000 x22: 0000000000000000 x21: ffff80000d5eb4a0 x20: ffff0000cc2b5520 x19: ffff80000d8c8000 x18: 00000000000000c0 x17: ffff80000dd0b198 x16: ffff80000db49158 x15: ffff0000c7128000 x14: 0000000000000000 x13: 00000000ffffffff x12: ffff0000c7128000 x11: ff808000081c0d5c x10: 0000000000000000 x9 : 7c5041a976250900 x8 : 7c5041a976250900 x7 : ffff80000819545c x6 : 0000000000000000 x5 : 0000000000000080 x4 : 0000000000000001 x3 : 0000000000000000 x2 : 0000000000000000 x1 : 0000000100000000 x0 : 0000000000000000 Call trace: refcount_dec_and_lock+0x180/0x1ec lib/refcount.c:146 nilfs_put_root+0x30/0x80 fs/nilfs2/the_nilfs.c:797 nilfs_segctor_destroy fs/nilfs2/segment.c:2747 [inline] nilfs_detach_log_writer+0x3b8/0x4d0 fs/nilfs2/segment.c:2810 nilfs_put_super+0x28/0x9c fs/nilfs2/super.c:468 generic_shutdown_super+0x8c/0x190 fs/super.c:491 kill_block_super+0x30/0x78 fs/super.c:1427 deactivate_locked_super+0x70/0xe8 fs/super.c:332 deactivate_super+0xd0/0xd4 fs/super.c:363 cleanup_mnt+0x1f8/0x234 fs/namespace.c:1186 __cleanup_mnt+0x20/0x30 fs/namespace.c:1193 task_work_run+0xc4/0x14c kernel/task_work.c:177 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x26c/0xbe0 kernel/exit.c:795 do_group_exit+0x60/0xe8 kernel/exit.c:925 __do_sys_exit_group kernel/exit.c:936 [inline] __se_sys_exit_group kernel/exit.c:934 [inline] __wake_up_parent+0x0/0x40 kernel/exit.c:934 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline] invoke_syscall arch/arm64/kernel/syscall.c:52 [inline] el0_svc_common+0x138/0x220 arch/arm64/kernel/syscall.c:142 do_el0_svc+0x48/0x164 arch/arm64/kernel/syscall.c:206 el0_svc+0x58/0x150 arch/arm64/kernel/entry-common.c:636 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:654 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:581 irq event stamp: 9228 hardirqs last enabled at (9227): [] __up_console_sem+0xb0/0xfc kernel/printk/printk.c:264 hardirqs last disabled at (9228): [] el1_dbg+0x24/0x5c arch/arm64/kernel/entry-common.c:404 softirqs last enabled at (7974): [] local_bh_enable+0x10/0x34 include/linux/bottom_half.h:32 softirqs last disabled at (7972): [] local_bh_disable+0x10/0x34 include/linux/bottom_half.h:19 ---[